Note 9 - Business Segments (Tables)

9 Months Ended

Sep. 30, 2015

Segment Reporting [Abstract]

Schedule of Segment Reporting Information, by Segment [Table Text Block]

	Electricity		Product		Consolidated
	(Dollars in thousands)
Three Months Ended September 30, 2015:
Net revenue from external customers	$	97,245	$	65,607	$	162,852
Intersegment revenue		—		10,657		10,657
Operating income (loss)		28,346		18,133		46,479
Segment assets at period end *		2,103,754		182,579		2,286,333
* Including unconsolidated investments		—		—		—
Three Months Ended September 30, 2014:
Net revenue from external customers	$	102,506	$	37,736	$	140,242
Intersegment revenue		—		7,244		7,244
Operating income (loss)		32,411		11,377		43,788
Segment assets at period end *		2,083,715		88,198		2,171,913
* Including unconsolidated investments		1,339		—		1,339
Nine Months Ended September 30, 2015:
Net revenue from external customers	$	278,124	$	145,446	$	423,570
Intersegment revenue		—		41,314		41,314
Operating income (loss)		73,220		41,753		114,973
Segment assets at period end *		2,103,754		182,579		2,286,333
* Including unconsolidated investments		—		—		—
Nine Months Ended September 30, 2014:
Net revenue from external customers	$	289,015	$	121,266	$	410,281
Intersegment revenue		—		43,580		43,580
Operating income (loss)		72,850		35,839		108,689
Segment assets at period end *		2,083,715		88,198		2,171,913
* Including unconsolidated investments		1,339		—		1,339

Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Table Text Block]

	Three Months Ended September 30,						Nine Months Ended September 30,
	2015			2014			2015			2014
Revenue:
Total segment revenue	$	162,852		$	140,242		$	423,570		$	410,281
Intersegment revenue		10,658			7,244			41,314			43,580
Elimination of intersegment revenue		(10,658	)		(7,244	)		(41,314	)		(43,580	)
Total consolidated revenue	$	162,852		$	140,242		$	423,570		$	410,281
Operating income:
Operating income	$	46,479		$	43,788		$	114,973		$	108,689
Interest income		53			35			106			236
Interest expense, net		(17,748	)		(22,494	)		(54,435	)		(65,084	)
Foreign currency translation and transaction gains (losses)		1,296			(2,946	)		(641	)		(3,639	)
Income attributable to sale of equity interest		8,634			5,487			18,917			18,334
Gain from sale of property, plant and equipment		—			—			—			7,628
Other non-operating income (expense), net		(131	)		243			(1,523	)		649
Total consolidated income before income taxes and equity in income of investees	$	38,583		$	24,113		$	77,397		$	66,813